Russia has evacuated the last of its personnel from Syria, including from its Mediterranean naval base in Tartus, in a move that appears to underline Moscow's mounting concerns about the escalating crisis.

Russian media reported on Wednesday that they had confirmed the evacuation with officials in the country's military and foreign ministry. But there was no official confirmation of a claim from rebel Free Syrian Army sources that a Russian plane had been shot down and its pilot captured in the western Aleppo area.

The effective closure of the Tartus base would be a significant loss, though a 16-ship naval task force is still in the eastern Mediterranean. The base is Russia's only foothold in the Middle East.

Neighbouring Cyprus has, however, made its ports available to the Russian fleet. Cypriot media have reported that the government may allow Russia to use its base at Paphos to host military aircraft.

News that Russian forces had pulled out of Syria came in an interview with Mikhail Bogdanov, the deputy foreign minister, in an interview with the newspaper al-Hayat last week.

"Today, the Russian defence ministry does not have a single person in Syria," he said. He described Tartus as a "technical facility for maintaining ships sailing in the Mediterranean."

The Vedomosti newspaper quoted an unnamed defence ministry official as saying: "We have neither servicemen nor civilians in Syria any more. Or Russian military instructors assigned to units of the Syrian regular army, for that matter."

But Vedomosti said the decision to remove defence ministry personnel did not include technical experts employed by the Syrian government to train its army to use Russian-issued weapons.

Russia Today, the Kremlin's English-language propaganda channel, said: "The withdrawal was prompted not only by the increased risks caused by the ongoing military conflict, but also by the fact that in the current conditions any incident involving Russian servicemen would likely have some unfavourable reaction from the international community."

Russia has been evacuating its citizens from Syria for weeks. Bogdanov said that about 30,000 Russians live throughout the country, some in rebel-held areas. The Interfax news agency reported that 128 Russians and citizens of other former Soviet republics left Syria on Wednesday on planes that had delivered what was described as humanitarian supplies the previous day.

Russia remains Assad's last major ally, alongside Iran. It has repeatedly blocked US-led attempts to sanction Bashar al-Assad's regime via the UN. Russia and the US failed to agree in talks this week on convening a peace conference in Geneva between the Syrian government and opposition.

The pullout from Tartus is unlikely to interfere with the delivery of Russian air defence and anti-ship missiles to Syria. Bogdanov defended the shipments of arms as legal and arranged under an existing contract. Asked when the deliveries would begin, he replied that that was a decision for the "supreme command".